Latent gammaherpesvirus (?HV) infection exists in >90% of the world's population, and is associated with chronic inflammation and numerous malignancies. There is a significant gap in knowledge regarding cellular outcomes of primary infection, and this limits the development of therapeutics to prevent latent infection. We hypothesize that outcome of primary ?HV infection is dependent on the cell type infected. The experiments outlined here will enhance knowledge of the early events in ?HV infection, using murine gammaherpesvirus 68 (?HV68) as a model. We will focus our investigation on B cells and endothelial cells (ECs) because they both have roles in chronic ?HV infection and are the transformed cell types of many ?HV-associated tumors. Our preliminary data indicate that outcome of yHV68 infection is very different in B cell and ECs, and that neither infection adheres to the current working model of lytic replication versus latent infection. Aim 1 of this project is to investigate the early outcome of yHV68 infection in B cells. Analyzing both in vitro and in vivo infection, we will make use of labeled virus to determine how efficiently yHV68 genome localizes to the nucleus of infected B cells. We also will determine how robustly yHV68 genome is transcribed in infected B cells via a luciferase reporter and PCR analysis. Aim 2 of this project is to determine the contribution of autophagy to in vitro EC infection outcome. We will determine if EC survivors of yHV68 infection are undergoing autophagy, and what effect inhibiting autophagy has on infection outcome. We also will test candidate autophagy-associated viral genes for their role in EC infection outcome. Aim 3 of this project is to characterize EC outcome of yHV68 infection in vivo. We will detect and characterize infected ECs in tissues from infected mice using immunohistochemistry, in situ hybridization, and RT-PCR. Relevance: Chronic yHV infection exists in >90% of the population and is associated with the development of many different cancers. Currently we do not know enough about the early outcomes of yHV infection to design drugs for reducing the prevalence of chronic, disease-associated infection. These experiments are important because they will determine early outcomes of yHV infection in relevant specific cell types.